Final answer:
Franklin D. Roosevelt's "Four Freedoms" speech warned of the pressing Nazi threat to global democracy and urged the United States to bolster the democratic world against aggression. As part of the war effort, the US expanded its military and provided vital support to allies, laying the groundwork for a post-war world based on democratic freedoms.
Step-by-step explanation:
In Franklin D. Roosevelt's “Four Freedoms” speech, he elucidates the notion that Nazi aggression poses a significant threat to democracy across the globe. He underscores the urgency of the situation by highlighting that events in Europe are not isolated and significantly affect the future and safety of the United States and other democracies worldwide. Roosevelt details the grim reality of an assault on democratic nations by arms and propaganda, an assault that, if not countered, threatens to dominate the populations and resources of not just Europe but also Asia, Africa, and Australasia.
Roosevelt's speech rallies the American public and Congress towards action, resulting in a massive expansion of the military and a transition to a wartime economy. By aiding nations such as Greece and Turkey, and providing financial and material support to allies like Great Britain and Russia, the United States positions itself as both the arsenal and champion of democracy. Roosevelt's vision includes a post-war world founded on the Four Freedoms and a rejection of totalitarian regimes fueled by poverty and want, promoting a future where freedom and democracy prevail over fascism.
The Allied forces, understanding the immediate threat posed by Germany, strategized to minimize its impact. The Atlantic Charter, a declaration of principles set by Roosevelt and Churchill, serves as a defense against fascism and an affirmation of their commitment to freedom and democracy. These combined efforts were pivotal in shaping the course of World War II and setting the stage for a peaceful post-war world's architecture.